Andreas Schmitz <a(dot)schmitz(at)cityweb(dot)de> writes:
> I have a problem with select lower() using capital letters with diaeresis. I
> tried with encoding SQL_ASCII und UNICODE.
upper/lower currently only work with single-byte characters, so you need
to use one of the LATINn database encodings rather than UNICODE if you
want this functionality.
regards, tom lane